Tunable optoelectronic oscillator based on a chirped Mach-Zehnder modulator

Abstract

Realization of a wideband tunable optoelectronic oscillator based on a chirped Mach-Zehnder modulator (MZM) and a chirped fiber Bragg grating is proposed and demonstrated. By simply adjusting the direct-current bias of the chirped MZM, the frequency of the oscillating signal is tuned. A theoretical model is established, then verified by an experiment. A high-purity microwave signal with a tunable frequency from 5.8 to 11.8 GHz is generated. The single-sideband phase noise of the generated signal is −112.6 dBc∕Hz at a frequency offset of 10 kHz.

Frequency Scanning Multibeamforming Method Based on CFBG Photonic Microwave Oscillation

“…Te system design block diagram is shown in Figure 3. Te frequency source (inside the dashed boxed) is given by a CFBG-based two-loop photoelectric oscillator [8], which is mainly composed of a light source, a polarizer, a polarization combiner, single mode fbers, a photodiode, a radio frequency amplifer, a chirped grating, and a Mach-Zehnder external modulator (MZM) [9][10][11][12][13]. Te tuneable photoelectric oscillator can be tuned by using a chirped fber Bragg grating (CFBG) as a photonic flter to select the frequency of the oscillation mode [14][15][16].…”